Operation of fire extinguishers, etc



Patented Jan. 29, 1924.

UNITED TEE HARVEY G. ELLEDGE, 01" BETHEL TOWNSHIP, NEAR PITTSBURGH, PENNSYLVANIA.

OPERATION OF FIRE EXTINGUISHERS, ETC.

No Drawing.

To all whom it may concern Be it known that I, HARVEY G. ELLEnGn, a citizen of the l nited States. residing at Bethel Township, near Pittsburgh, in the 5 county of Allegheny. State of Pennsylvania,

have invented certain new'aud useful lmprovements in the Operation of Fire Extinguishers, Etc: and I do hereby declare the following to be a full. clear, and exact description 'of the invention, such as will enable others skilled in the art to which itappertains to make and use the same.

' This invention relates to improvements in fire extinguishers and particularly in self 15, ressure generating fire extinguishers. and

in their charging and operation.

, in the charging of self pressure generating fire extin uishers it has been the practice to add a su cient quantity of sodium bicarbonate and dissolve'it in suiiicient water to fill the fire extinguisheig'except for such volume as was to be occupied by a separate chamber containing a mineral acid or a water solution with an acid salt. which mineral acid or acid salt solution was kept separate from the sodium bicarbonate solution until the fire extinguisher was to be brought into action. When the fire extinguisher was to be used, the two solutions a0 were by suitable means brought into intimate contact.

The use of such materialsin'self pressure generating fire extinguishers requires that the separate chamber containing the acid or acid salt solution be constructed of acid resisting material, and usually a glass bottle or lead cylinder has been used. Moreover, the construction of the mechanical devices for subsequent mixing of the contents of 49 the main and separate ghambers has been more or less expensive:

The fire extinguishing composition employed in the resent invention is free from acids and acidcompounds, and under the conditions of use. is relatively non-corrosive to iron, brass and solder. The fire extinguishers may therefore be made of cheaper construction than in the case of extinguishers used with acid reagents.

The improved fire extinguishing composition employed in the present invention is made up essentially of sodium bicarbonate and calcium chloride. When these substances are-added to water they react with 65 the format on of calcium carbonate, sodium Application filed December 28. 1922. Serial No. 609,512.

chloride, carbon dioxide and water, approximately one-half of the carbon dioxide of the sodium bicarbtmate being set free by the reaction. Calcium chloride is itself a neutral salt. As commercially produced. it contains a trace of calcium hydroxide but it is free from acid reaction and is substantially non-corrosive under the conditions of use.

Since the sodium bicarbonate and calcium chloride are without efiect on each other when water is absent, they may be provided as a dry composition by mixing the ingredients together in weighed quantities calculated to give the desired pressure for the capacity of the individual fire extinguisher. The dry mixture can then be placed in a Waterproof container, such as one which is easily puncturable or which is covered with a thin easily puncturable waterproof paper cap; and such a waterproof container can be placed within the extinguisher so that it will float on the water; and provision may be made for puncturing the container or the paper cap when the fire extinguisher is to be brought into play, thus permitting access of water to the composition with the resulting reaction of the character above mentioned.

For example, if the fire extinguisher is of two gallon capacity, and if a pressure of around or lbs. per sq. in. is desired, a mixture of 1 1b. of commercial, calcium chloride and 1 lb. of sodium bicarbonate may be used and placed in the waterproof container to be inserted as a charge for the fire extinguisher; or the amount 0 the composition can be increased or decreased according 'to the capacity of the fire extinguisher and the expelling pressure desired. The fire extinguishing composition can be made up in large amounts or in individual containers, each representing a predetermined charge for a fire extinguisher of given size. Since calcium chloride is hygroscopic, it is important to protect the composition after admixture from atmospheric moisture as well as from contact with the water in the extinguishen' This can readily be accomplished by using waterproof containers in which the composition is kept until it is to be used in the extinguisher.

In the operation of the extinguisher, the composition previously prepared a. dry state may be used as such, in predetermined amount, and the pressure generated by puncturing the container or otherwise permitting access of water thereto. action which takes place immediately serves to generate the necessary pressure within the extinguisher so that the extinguisher can be readily operated without fear or danger of corrosion and without the necessity of providing a seperate acid-proof container within the extinguisher for holding an acid or acid salt solution.

Instead of providing a dry composition and operating the extinguishers in the manner above described, the commercial calcium chloride which contains a trace of calcium hydroxide may be dissolved in water in the chamber of the fire extinguisher, and the alkaliunetal bicarbonate contained in a waterproof container which may be floated on the solution and opened by a mechanical de vice when the fire extinguisher is to be brought into play. lVhen the container is punctured or otherwise opened to permit access of the calcuim chloride solution, reaction will immediately take place with the generation of the pressure desired. By operating an extinguisher in this way, advantage is taken of the anti-freezing properties of the calcium chloride solution so that the extinguishers can be operated even at low temperatures without danger of freezing.

"Vhen the fire extinguishers are to be used in localities or during seasonable periods wherein protection against freezing is not of importance, the alkali-metal bicarbonate may be dissolved in the water of the chamber of the fire extinguisher and the calcium chloride placed in a waterproof container to float on the solution or otherwise bemaintained within the extinguisher until the extinguisher is to be used; whereupon the puncturing or opening of the container by mechanical. or other means will permit access of the alkali bicarbonate solution to the calcium chloride, or will'discharge the calcium chloride into the solution, and thereby bring about reaction and the development of the desired pressure.

- When the fire extinguisher is to be brought into play, the sealed container will be punctured or opened by mechanical means or otherwise so that carbon dioxide will be generated by the reaction between the alkali icarbontate and the calcuim chloride in the presence ofwater. The formation of carbon dioxide in this way will generate the pres sure required for expelling the liquid from.

the extinguisher.-

One of the important and valuable applications and embodiments of the invention in-.

cludes the use of frothjorming and foam stabilizing ingredients tn the fire extinguishing composition. When these ingredients are present the composition is useful" particularly in combating oil fires and for other purposes where the formation of a stable The reblanketof foam is desired. The composi-, tion may thus be made up of sodium bicarbonate, calcium chloride and froth forming and foam stabilizing ingredients such a glue. saponin. black liquor (a by-product of wood pulp manufacture), licorice, quillia, tan bark residues and other vegetable extracts. Such compositions properly compounded will produce a blanket or carbon dioxide foam which will serve to cover burning volatile liquids to which the composition may be applied.

For use in oil refineries and in other places where oil fires are to be combated. the firc extinguishers may be much larger in size than the hand operated extinguishers above described. They may be mounted on trucks or on railroad cars, in the caseof large extinguishers, or they may be portable or of smaller type, such as those above mentioned. In all of these extinguishers the composition enables the extinguishers to be self pressure generating in the manner previously described.

With larger extinguishers containing larger amounts of the chemicals and of-water, a considerable period of time may be required in discharging the entire contents of the extinguisher and the operation of the extinguisher can be modified by utilizing a part of the carbon dioxide generated for giving the necessary pressure and in causing the remaining ingredients to mix as the composition leaves the extinguisher sothat further generation of carbon dioxide will take placeby further reaction after the liquid leaves the extinguisher.

It will thus be seen that the invention provides an improved method of operation of fire extinguishers in which the generation of pressure takes place without the use of acids or acid reagents and without danger of corrosion of the extinguisher. In the operation of the extinguisher the ingredients used may themselves be previously admixed in a dry state or one of the ingredients kept in a dry state while the other is dissolved in .the water. and the extinguisher will be brought into operation by opening or puncturing the sealed container and permitting the reagents to'act in the presence of water to generate the necessary pressure.

When the generator is operated, the water forced from the generator will be free from acids and acid reagents and will not therefore be corrosive where applied for fire extinction. In operation, therefore, the extinguisher is more advantageous than extinguishers in which acids are used and in which an excess of acid may be present in the water discharged from the extinguisher in case full opportunity has not been provided for. the reaction of the acid and bicarbonate or in case of local over concentration of acid in any portion of the water discharged, due,

1,4se,ecs

l. The improvement in the operation of.

fire extinguishers which comprises supplymg to the fire extinguisher sodium bicarbonate and calcium chloride and causing the same to react in the in the extinguisher.

2. The improvement in the operation of fire extinguishers which comprises supplying to the extinguisher Water, calcium chlopresence of the water 7 ride and sodium bicarbonate, at least one of said materials (3. e., calcium chloride and sodium bicarbonate) being provided in a Waterproof container,. whereby the generator can be brought into operation by open ing the container and permitting the sodium bicarbonate and calcium chloride to react in the presence of Water.

3. The improvement in the operation of fire extinguishers which comprises supplying sodium bicarbonate and calcium chloride in the form of a dry composition and in a Waterproof container and bringing the extinguisher into operation by opening the container and permitting access of water to the composition, whereby the composition reacts with the production of carbon dioxide Without the presence during the reaction of acid reagents.

4. The improvement in the operation of fire extinguishers which comprises supplying to the extinguisher a solution of sodium bicarbonate in Water and dry calcium chloride in a waterproof container and bringing the extinguisher into operation by opening the container and permitting access of the calcium chloride and sodium bicarbonate solution.

5. The improvement in the operation of fire extinguishers which comprises supplying to the extinguisher a solution of calcium chloride in water and dry sodium bicarbonate in a Waterproof container and bringing the extinguisher into operation by opening the container and permittin access of the sodium bicarbonate and ca ClUJll chloride solution.

6. The improvement in the operation of fire extinguishers which comprises sup-' plying to the fire extinguisher sodium bicarbonate, calcium chloride and froth foaming and foam stabilizing ingredients and causing the bicarbonate and chloride to react in the presence of the Water in the extinguisher.

In testimony whereof I afix my signature.

HARVEY G. ELLEDGE, 

